#pragma ident "$Id$"



/**
 * @file RinexObsFilterOperators.hpp
 * Operators for FileFilter using Rinex observation data
 */

#ifndef GPSTK_RINEXOBSFILTEROPERATORS_HPP
#define GPSTK_RINEXOBSFILTEROPERATORS_HPP

//============================================================================
//
//  This file is part of GPSTk, the GPS Toolkit.
//
//  The GPSTk is free software; you can redistribute it and/or modify
//  it under the terms of the GNU Lesser General Public License as published
//  by the Free Software Foundation; either version 2.1 of the License, or
//  any later version.
//
//  The GPSTk is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU Lesser General Public License for more details.
//
//  You should have received a copy of the GNU Lesser General Public
//  License along with GPSTk; if not, write to the Free Software Foundation,
//  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
//
//  Copyright 2004, The University of Texas at Austin
//
//============================================================================

//============================================================================
//
//This software developed by Applied Research Laboratories at the University of
//Texas at Austin, under contract to an agency or agencies within the U.S.
//Department of Defense. The U.S. Government retains all rights to use,
//duplicate, distribute, disclose, or release this software.
//
//Pursuant to DoD Directive 523024
//
// DISTRIBUTION STATEMENT A: This software has been approved for public
//                           release, distribution is unlimited.
//
//=============================================================================






#include "FileFilter.hpp"
#include "RinexObsData.hpp"
#include "RinexObsHeader.hpp"

#include <set>
#include <algorithm>

namespace gpstk
{
/** @addtogroup RinexObs */
//@{

/// This compares all elements of the RinexObsData with less than
/// (only for those fields which the two obs data share).
struct RinexObsDataOperatorLessThanFull :
    public std::binary_function<gpstk::RinexObsData,
    gpstk::RinexObsData, bool>
{
public:
    /// The set is a set of RinexObsType that the two files have in
    /// common.  This is easily generated with the set_intersection
    /// STL function.  See difftools/rowdiff.cpp for an example.
    RinexObsDataOperatorLessThanFull
    (const std::set<gpstk::RinexObsType>& rohset)
        : obsSet(rohset)
    {}

    bool operator()(const gpstk::RinexObsData& l,
                    const gpstk::RinexObsData& r) const
    {
        // compare the times, offsets, then only those elements
        // that are common to both.  this ignores the flags
        // that are set to 0
        if (l.time < r.time)
            return true;
        else if (l.time == r.time)
        {
            if (l.epochFlag < r.epochFlag)
                return true;
            else if (l.epochFlag == r.epochFlag)
            {
                if (l.clockOffset < r.clockOffset)
                    return true;
                else if (l.clockOffset > r.clockOffset)
                    return false;
            }
            else
                return false;
        }
        else
            return false;

        // for the obs, first check that they're the same size
        // i.e. - contain the same number of PRNs
        if (l.obs.size() < r.obs.size())
            return true;

        if (l.obs.size() > r.obs.size())
            return false;

        // then check that each PRN has the same data for each of the
        // shared fields
        gpstk::RinexObsData::RinexSatMap::const_iterator lItr =
            l.obs.begin(), rItr;

        gpstk::SatID sat;

        while (lItr != l.obs.end())
        {
            sat = (*lItr).first;
            rItr = r.obs.find(sat);
            if (rItr == r.obs.end())
                return false;

            gpstk::RinexObsData::RinexObsTypeMap
            lObs = (*lItr).second,
            rObs = (*rItr).second;

            std::set<gpstk::RinexObsType>::const_iterator obsItr =
                obsSet.begin();

            while (obsItr != obsSet.end())
            {
                gpstk::RinexDatum lData, rData;
                lData = lObs[*obsItr];
                rData = rObs[*obsItr];

                if (lData.data < rData.data)
                    return true;

                if ( (lData.lli != 0) && (rData.lli != 0) )
                    if (lData.lli < rData.lli)
                        return true;

                if ( (lData.ssi != 0) && (rData.ssi != 0) )
                    if (lData.ssi < rData.ssi)
                        return true;

                obsItr++;
            }

            lItr++;
        }

        // the data is either == or > at this point
        return false;
    }

private:
    std::set<gpstk::RinexObsType> obsSet;
};

/// This is a much faster less than operator for RinexObsData,
/// only checking time
struct RinexObsDataOperatorLessThanSimple :
    public std::binary_function<gpstk::RinexObsData,
    gpstk::RinexObsData, bool>
{
public:
    bool operator()(const gpstk::RinexObsData& l,
                    const gpstk::RinexObsData& r) const
    {
        if (l.time < r.time)
            return true;
        return false;
    }
};

/// This simply compares the times of the two records
/// for equality
struct RinexObsDataOperatorEqualsSimple :
    public std::binary_function<gpstk::RinexObsData,
    gpstk::RinexObsData, bool>
{
public:
    bool operator()(const gpstk::RinexObsData& l,
                    const gpstk::RinexObsData& r) const
    {
        if (l.time == r.time)
            return true;
        return false;
    }
};

/// Combines RinexObsHeaders into a single header, combining comments
/// and adding the appropriate RinexObsTypes.  This assumes that
/// all the headers come from the same station for setting the other
/// header fields. After running touch() on a list of RinexObsHeader,
/// the internal theHeader will be the merged header data for
/// those files and obsSet will be the set of RinexObsTypes that
/// will be printed to the file.
struct RinexObsHeaderTouchHeaderMerge :
    public std::unary_function<gpstk::RinexObsHeader, bool>
{
public:
    RinexObsHeaderTouchHeaderMerge()
        : firstHeader(true)
    {}

    bool operator()(const gpstk::RinexObsHeader& l)
    {
        if (firstHeader)
        {
            theHeader = l;
            firstHeader = false;
        }
        else
        {
            std::set<gpstk::RinexObsType> thisObsSet,
                tempObsSet;
            std::set<std::string> commentSet;
            obsSet.clear();

            // insert the comments to the set
            // and let the set take care of uniqueness
            copy(theHeader.commentList.begin(),
                 theHeader.commentList.end(),
                 inserter(commentSet, commentSet.begin()));
            copy(l.commentList.begin(),
                 l.commentList.end(),
                 inserter(commentSet, commentSet.begin()));
            // then copy the comments back into theHeader
            theHeader.commentList.clear();
            copy(commentSet.begin(), commentSet.end(),
                 inserter(theHeader.commentList,
                          theHeader.commentList.begin()));

            // find the set intersection of the obs types
            copy(theHeader.obsTypeList.begin(),
                 theHeader.obsTypeList.end(),
                 inserter(thisObsSet, thisObsSet.begin()));
            copy(l.obsTypeList.begin(),
                 l.obsTypeList.end(),
                 inserter(tempObsSet, tempObsSet.begin()));
            set_intersection(thisObsSet.begin(), thisObsSet.end(),
                             tempObsSet.begin(), tempObsSet.end(),
                             inserter(obsSet, obsSet.begin()));
            // then copy the obsTypes back into theHeader
            theHeader.obsTypeList.clear();
            copy(obsSet.begin(), obsSet.end(),
                 inserter(theHeader.obsTypeList,
                          theHeader.obsTypeList.begin()));
        }
        return true;
    }

    bool firstHeader;
    gpstk::RinexObsHeader theHeader;
    std::set<gpstk::RinexObsType> obsSet;
};

//@}

}


#endif
